@inproceedings{37436, author = {{Beimdiek, Janis and Prill, Friedrich and König, Mario and Müller, Mirjam and Hartmann, Ingo and Schmid, Hans-Joachim}}, booktitle = {{13th World Filtration Congress Proceedings}}, location = {{San Diego}}, title = {{{Combined filtration process for biomass combustion plants to comply with legal requirements (oral presentation)}}}, year = {{2022}}, } @inproceedings{37426, author = {{Beimdiek, Janis and Schmid, Hans-Joachim}}, booktitle = {{IAC 2022 Book of Abstracts}}, location = {{Athens}}, title = {{{A combined flue gas cleaning system with a novel entrained flow SCR using online synthesized catalyst particles (Poster)}}}, year = {{2022}}, } @inproceedings{37430, author = {{Beimdiek, Janis and Schmid, Hans-Joachim}}, location = {{Zürich}}, title = {{{Novel entrained flow SCR using online synthesized catalyst particles in flue gas cleaning systems (oral presentation)}}}, year = {{2022}}, } @article{25142, abstract = {{Additive Manufacturing provides the opportunity to produce tailored and complex structures economically. The use of lattice structures in combination with a thermoplastic elastomer enables the generation of structures with configurable properties by varying the cell parameters. Since there is only little knowledge about the producibility of lattice structures made of TPE in the laser sintering process and the resulting mechanical properties, different kinds of lattice structures are investigated within this work. The cell type, cell size and strut thickness of these structures are varied and analyzed. Within the experimental characterization of Dodecahedron-cell static and cyclic compression tests of sandwich structures are focused. The material exhibits hyperelastic and plastic properties and also the Mullins-Effect. For the later design of real TPE structures, the use of numerical methods helps to reduce time and costs. The preceding experimental investigations are used to develop a concept for the numerical modeling of TPE lattice structures.}}, author = {{Kummert, Christina and Schmid, Hans-Joachim and Risse, Lena and Kullmer, Gunter}}, issn = {{0884-2914}}, journal = {{Journal of Materials Research}}, title = {{{Mechanical characterization and numerical modeling of laser-sintered TPE lattice structures}}}, doi = {{10.1557/s43578-021-00321-3}}, year = {{2021}}, } @inproceedings{23760, abstract = {{The laser sintering process has been a well-established AM process for many years. Disadvantages of LS are the low material variety and the thermal damage of the unprocessed material. The low temperature laser sintering attacks at this point and processes powder material at a build chamber temperature lower than the recrystallization temperature. This drastic reduction in temperature results in significantly less thermal damage to the material. This work deals with the low temperature laser sintering of Polyamide 12 (PA12) on a commercial, unmodified laser sintering system to compare it to standard laser sintered PA12 and to create the basis for low temperature laser sintering of high temperature materials on such a system. First results by changing the exposure parameters and by fixing parts on a building platform show a processing of PA12 on an EOS P396 at a build chamber temperature less than 100 °C instead of standard approx. 175 °C.}}, author = {{Menge, Dennis and Schmid, Hans-Joachim}}, keywords = {{Low Temp LS, Low Temperature Laser Sintering, Polyamid 12}}, location = {{Austin, TX}}, title = {{{Low Temperature Laser Sintering on a Standard System: First Attempts and Results with PA12}}}, year = {{2021}}, } @inproceedings{30364, author = {{Tischendorf, Ricardo and Schmid, Hans-Joachim and Bieber, M. and Reddemann, M. and Kneer, R. and Fröde, F. and Grenga, T. and Pitsch, H.}}, location = {{Paderborn}}, title = {{{Einfluss der Zerstäubung auf die Partikelsynthese in Sprayflammen}}}, year = {{2021}}, } @misc{24202, author = {{Pawelczyk, Sebastian and Jesinghausen, Steffen and Schmid, Hans-Joachim}}, title = {{{Charakterisierung des Fließverhaltens von Frischbeton – Entwicklung eines adaptiven Rheometers (ACCR) und Einfluss von Maßnahmen zur Sedimentationsprävention}}}, year = {{2021}}, } @inproceedings{30225, author = {{Rüther, Moritz Johannes and Schulze, Dietmar and Schmid, Hans-Joachim}}, location = {{digital}}, title = {{{Flowability Measurements of Different SLS Materials at Elevated Temperatures with a Modified Schulze Ring Shear Tester}}}, year = {{2021}}, } @inproceedings{24160, abstract = {{In automotive and other fields of application media-carrying components often have complex, flow-optimized geometries and are made of plastics for reasons of weight and cost. Therefore, the laser sintering technology is predestinated to manufacture these components as it offers a very high degree of design freedom and good mechanical properties. For industrial applications the long-term properties of the SLS material in contact with liquid media are important and were therefore investigated for PA12, PP and PA613. Hereby, different media such as motor oil or Glysantin based coolant were tested with different temperatures and immersion times of up to 26 weeks. The mechanical properties were tested after immersion and compared to injection molded samples. Furthermore, laser sintering design guidelines for media-carrying components were developed. These guidelines for instance include the minimum wall thickness to ensure media tightness and the removal of powder from channels with a high length to diameter ratio.}}, author = {{Kletetzka, Ivo and Kummert, Christina and Schmid, Hans-Joachim}}, booktitle = {{Proceedings of the 32nd Annual International Solid Freeform Fabrication Symposium}}, location = {{Austin}}, publisher = {{Laboratory for Freeform Fabrication and University of Texas}}, title = {{{Laser Sintering Design Guidelines for media transmitting Components}}}, doi = {{http://dx.doi.org/10.26153/tsw/17548}}, volume = {{32}}, year = {{2021}}, } @article{26095, abstract = {{Luftreiniger werden derzeit häufig als mögliches Hilfsmittel zur Minimierung des Infektionsrisikos im Rahmen der COVID-19-Pandemie diskutiert. Dabei taucht oft die Frage auf, ob Luftreiniger grundsätzlich in der Lage sind, Viren oder virenbeladene Tröpfchen abzuscheiden. Ziel dieses Artikels ist es, die wesentlichen Grundlagen der Wirkungsweise von Luftreinigern und Filtern zu beschreiben, Methoden zur Messung der Reinigungswirkung im Größenbereich von Viren und virenbeladenen Tröpfchen aufzuzeigen sowie typische Szenarien zum Betrieb von Luftreinigern in einem mathematischen Modell zu erfassen. Darauf basierend können die Möglichkeiten und Grenzen von Luftreinigern für reale Anwendungsfälle besser eingeschätzt werden.}}, author = {{Schumacher, Stefan and Asbach, Christof and Schmid, Hans-Joachim}}, issn = {{0949-8036}}, journal = {{Gefahrstoffe}}, pages = {{16--28}}, title = {{{Effektivität von Luftreinigern zur Reduzierung des COVID-19-Infektionsrisikos/ Efficacy of air purifiers in reducing the risk of COVID-19 infections}}}, doi = {{10.37544/0949-8036-2021-01-02-18}}, year = {{2021}}, } @inproceedings{27553, author = {{Ludwig, Janis and Schmid, Hans-Joachim}}, title = {{{Synthese und asymmetrische Funktionalisierung von submikronen Janus-Polymer-Partikeln in der Gasphase (Poster)}}}, year = {{2021}}, } @inproceedings{24475, author = {{Neukötter, Moritz and Jesinghausen, Steffen and Schmid, Hans-Joachim}}, location = {{Online}}, title = {{{Theoretische Beschreibung des Tropfenbildungsprozesses bei der Filament Extension Atomization: Entwicklung eines Vorhersagemodells für die Tropfengröße (Poster)}}}, year = {{2021}}, } @inproceedings{30221, author = {{Neukötter, Moritz and Jesinghausen, Steffen and Schmid, Hans-Joachim}}, location = {{Online}}, title = {{{Filament Extension Atomization – A novel Process for Powder Production? (Presentation)}}}, year = {{2021}}, } @inproceedings{27551, author = {{Ludwig, Janis and Kykal, Carsten and Schmid, Hans-Joachim}}, booktitle = {{Book of abstracts for the 2021 European Aerosol Conference}}, keywords = {{aerosol spreading, SARS-CoV-2, indoor air filtration}}, title = {{{Assessing spreading and removal of virus laden aerosols in different settings using an aerosol method (oral presentation)}}}, year = {{2021}}, } @techreport{24943, author = {{Menge, Dennis and Klippstein, Sven Helge and Schmid, Hans-Joachim}}, pages = {{130}}, title = {{{Additive Leichtbaustrukturen für die Flugzeugkabine}}}, year = {{2020}}, } @article{24241, abstract = {{For gas phase nanoparticle production, hot wall reactors are widely used. In this article, we will describe the fundamental design considerations for a hot wall reactor system able to produce oxide nanoparticles. The system is outstanding in its ability to produce mostly spherical nanoparticles at particle sizes of up to 100 nm and even larger at mass outputs in the order of grams per hour by being able to rapidly quench the aerosol. While high production rates or larger particle sizes are already easily obtained with hot wall reactors, it is very challenging to produce these spherical particles at high mass rates. We will show in this research that the temperature and the particle number concentration are the major aspects influencing the particle morphology at the end of the process. Investigation on the performance of the setup shows good control over the temperature and the particle production stability. A representative particle characterization using SEM and scanning mobility particle sizer showed that particles are mostly spherical, while the particle size distribution had a geometric standard deviation close to 1.5. In addition to the aspects mentioned above, a possibility to manipulate the aggregation downstream of the reactor is to be presented as well. We found that applying electrical charges to the aerosol particles (in opposite polarity) can significantly foster aggregation.}}, author = {{Rasche, David B. and Tigges, Lena and Schmid, Hans-Joachim}}, journal = {{Review of Scientific Instruments}}, pages = {{055104}}, publisher = {{AIP Publishing}}, title = {{{An Apparatus to Synthesize Ceramic Nanoparticles with a Precisely Adjusted Temperature History and a Significant Mass Output}}}, doi = {{10.1063/1.5133438}}, volume = {{91}}, year = {{2020}}, } @inproceedings{22182, author = {{Kummert, Christina and Diekmann, Wolfgang and Tews, Katrin and Schmid, Hans-Joachim}}, booktitle = {{29th Annual International Solid Freeform Fabrication Symposium}}, pages = {{735--744}}, title = {{{Influence of Part Microstructure on Mechanicl Properties of PA6X Laser Sintered Specimens}}}, doi = {{http://utw10945.utweb.utexas.edu/sites/default/files/2019/063%20Influence%20of%20Part%20Microstructure%20on%20Mechanical%20Pro.pdf}}, volume = {{29}}, year = {{2020}}, } @inproceedings{25062, author = {{Tischendorf, Ricardo and Schmid, Hans-Joachim and Bieber, M. and Reddemann , M. and Kneer, R. and Fröde, F. and Grenga, T. and Pitsch, H.}}, location = {{Duisburg}}, publisher = {{4th International Symposium Gas‐Phase Synthesis of Functional Nanomaterials}}, title = {{{Influence of differing nozzle configurations on the final particle characteristics and particle structure evolution in spray flames}}}, year = {{2020}}, } @article{21949, abstract = {{This paper presents the results of an interlaboratory study of the rheological properties of cement paste and ultrasound gel as reference substance. The goal was to quantify the comparability and reproducibility of measurements of the Bingham parameters yield stress and plastic viscosity when measured on one specific paste composition and one particular ultrasound gel in different laboratories using different rheometers and measurement geometries. The procedures for both in preparing the cement paste and carrying out the rheological measurements on cement paste and ultrasound gel were carefully defined for all of the study’s participants. Different conversion schemes for comparing the results obtained with the different measurement setups are presented here and critically discussed. The procedure proposed in this paper ensured a reasonable comparability of the results with a coefficient of variation for the yield stress of 27% and for the plastic viscosity of 24%, despite the individual measurement series’ having been performed in different labs with different rheometers and measurement geometries.}}, author = {{Haist, Michael and Link, Julian and Nicia, David and Leinitz, Sarah and Baumert, Christian and von Bronk, Tabea and Cotardo, Dario and Eslami Pirharati, Mahmoud and Fataei, Shirin and Garrecht, Harald and Gehlen, Christoph and Hauschildt, Inga and Ivanova, Irina and Jesinghausen, Steffen and Klein, Christopher and Krauss, Hans-W. and Lohaus, Ludger and Lowke, Dirk and Mazanec, Oliver and Pawelczyk, Sebastian and Pott, Ursula and Radebe, Nonkululeko W. and Riedmiller, Joachim Jürgen and Schmid, Hans-Joachim and Schmidt, Wolfram and Secrieru, Egor and Stephan, Dietmar and Thiedeitz, Mareike and Wilhelm, Manfred and Mechtcherine, Viktor}}, issn = {{1359-5997}}, journal = {{Materials and Structures}}, keywords = {{Rheology, Wall Slip, Slip, apparent slip, suspension, cement, concrete}}, title = {{{Interlaboratory study on rheological properties of cement pastes and reference substances: comparability of measurements performed with different rheometers and measurement geometries}}}, doi = {{10.1617/s11527-020-01477-w}}, year = {{2020}}, } @article{21948, abstract = {{Since suspensions (e.g., in food, cement, or cosmetics industries) tend to show wall slip, the application of structured measuring surfaces in rheometers is widespread. Usually, for parallel-plate geometries, the tip-to-tip distance is used for calculation of absolute rheological values, which implies that there is no flow behind this distance. However, several studies show that this is not true. Therefore, the measuring gap needs to be corrected by adding the effective gap extension δ to the prescribed gap height H in order to obtain absolute rheological properties. In this paper, we determine the effective gap extension δ for different structures and fluids (Newtonian, shear thinning, and model suspensions that can be adjusted to the behavior of real fluids) and compare the corrected values to reference data. We observe that for Newtonian fluids a gap- and material-independent correction function can be derived for every measuring system, which is also applicable to suspensions, but not to shear thinning fluids. Since this relation appears to be mainly dependent on the characteristics of flow behaviour, we show that the calibration of structured measuring systems is possible with Newtonian fluids and then can be transferred to suspensions up to a certain particle content.}}, author = {{Pawelczyk, Sebastian and Kniepkamp, Marieluise and Jesinghausen, Steffen and Schmid, Hans-Joachim}}, issn = {{1996-1944}}, journal = {{Materials}}, keywords = {{wall slip prevention, effective gap height, parallel-plate system, structured surfaces, model suspensions, cement paste, fresh concrete}}, title = {{{Absolute Rheological Measurements of Model Suspensions: Influence and Correction of Wall Slip Prevention Measures}}}, doi = {{10.3390/ma13020467}}, year = {{2020}}, }